Path Traversal in Flightphp Core

CVE-2026-42549

Flight is an extensible micro-framework for PHP. Prior to 3.18.1, the make:controller CLI command calls mkdir(..., recursive: true) on a path built from the user-supplied controller name, before Nette's class-name validation runs. The class-file write is correctly rejected by Nette when the name contains /, but the recursive directory creation side effect is already committed — including directories located outside the project root through ../ traversal. This vulnerability is fixed in 3.18.1.

Vulnerability class: Path Traversal (Directory Traversal)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L.

EPSS exploit prediction

EPSS: 0.002 (4.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 4th percentile — 4.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-42549: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-42549?
CVE-2026-42549 is a medium-severity vulnerability in Flightphp Core, classified under Path Traversal. CVSS score: 4.4/10. Published 2026-05-13.
How severe is CVE-2026-42549?
Medium severity. CVSS v3 base score is 4.4 out of 10.